Press with sliding bolster and die clamp



Dec. 28, 1965 A. CLEMENTS 3,225,686

PRESS WITH SLIDING BOLSTER AND DIE CLAMP Filed Aug. 30, 1963 8Sheets-Sheet 1 F I G, INVENTOR.

HLBERT CLEMENTS HT TORNEYS Dec. 28, 1965 A. CLEMENTS 3,225,686

PRESS WITH SLIDING BOLSTER AND DIE CLAMP Filed Aug. 30, 1963 8Sheets-Sheet 2 FIG-8 INVENTOR.

ALBERT CLEMENTS H TTOfPNE Y5 Dec. 28, 1965 A. CLEMENTS 3,225,686

PRESS WITH SLIDING BOLSTER AND DIE CLAMP Filed Aug. 30, 1963 8Sheets-Sheet 5 INVENTOR. ALBERT CLEMEN 7'5 ATTORNEYS Dec. 28, 1965 A.CLEMENTS 3,225,686

PRESS WITH SLIDING BOLSTER AND DIE CLAMP Filed Aug. 30, 1963 8Sheets-Sheet 4 FIG-4 R1 A1 I x 7 7/0- Ln 5;

a I F- i- N -z 1 v INVENTOR.

r 7' r HLBEFPT CLEMENTS HTTOPNE Y5 Dec. 28, 1965 CLEMENTS 3,225,686

PRESS WITH SLIDING BOLSTER AND DIE CLAMP Filed Aug. 30, 1963 8Sheets-Sheet 5 -f l I Q INVENTOR.

HLBER T CLEMEN T5 Dec. 28, 1965 A. CLEMENTS PRESS WITH SLIDING BOLSTERAND DIE CLAMP Filed Aug. 30, 1963 8 Sheets-Sheet 6 FIG-ll NO I8 lOgm/mwp ATTORNEYS w W Fm 2 MN 6 T 5 NM i wi 0 me 2 a T 2 Win 0 6 12 W 6 6HI 21"! L A \N \X I] 2 Wm H 45 P i 61 d 2/ K 2 q. QMIM I r l Q H J \\\.1m 6 m m l M 4 6 M Dec. 28, 1965 A. CLEMENTS PRESS WITH SLIDING BOLSTERAND DIE CLAMP 8 Sheets-Sheet 7 Filed Aug. 30, 1963 FIG I4 INVENTOR.ALBERT C LEMENTS H W 5! h uw H TTOE'NE Y5 Dec. 28, 1965 A. CLEMENTSPRESS WITH SLIDING BOLSTER AND DIE CLAMP Filed Aug. 30, 1963 8Sheets-Sheet 8 i l V301. V301? INVENTOR.

HLBERT CLEMENTS HTTORNEY5 United States Patent 3 225 686 PRESS wrrnSLIDING aorsrnn AND Din CLAMP Albert Clements, Hamilton, Ohio, assignorto The Minster Machine Company, Minster, Ohio, a corporation or" @hioFiled Aug. 30, 1963, Ser. No. 305,693 19 (llainis. (Cl. 100-43) Thisinvention relates to press structures and is particularly concerned witha die clamping structure in connection with a sliding bolster press andan automatic slide adjustment.

Sliding bolster presses are known in the art and are employed where, forone reason or another, it is desirable completely to withdraw fromworking position in a press, at least the lower part of the die setafter a working stroke of the press. This might come about on account ofthe necessity of removing work members from the die or for otherreasons. Also, sliding bolster presses are employed where die changesare to be made because the bolster can readily be withdrawn from thepress with the entire die thereon and this facilitates the work ofremoving dies from the press and installing new dies in the press.

Sliding bolsters have also been used in die spotting presses for readilyremoving or changing dies.

A particular problem that has always existed in connection with pressesof this nature has been the operation or positioning and clamping ofdies in place on the bolster, and another particular problem has beeninitial positioning of the press platen and the clamping of the upperdie portion to the press platen.

The present invention proposes an arrangement for minimizing the timeand effort required to install dies in a press and to clamp the upperdie part to the press platen, and it is further proposed by the presentinvention to provide an improved sliding bolster arrangement for thepress.

In general, the press according to the present inventioin is designedaround what might be considered to be a conventional press frameconsisting of a bed, a head, uprights extending between the bed and thehead and a press platen slidably guided on the uprights. According tothe present invention at least one, and preferably two bolsters, areprovided which are slidably guided from working position on the pressbed out of the press bed to supporting means adjacent the press frame.Each bolster can thus be provided with a die set externally of the presswhich can then be moved into working position in the press and the upperportion of the die set attached to the press platen. The bolsters mayslide front to back or left to right through openings in the uprights.

According to this invention, the connecting of the upper portion of thedie set to the press platen is greatly facilitated by providing adetector arrangement that detects the height of the die set on thebolster and adjusts the press platen in conformity to the height of thedie set whereby manual adjustment of the press platen into position toclamp the upper portion of the die set thereto is eliminated or, atleast, greatly reduced.

The present invention also embodies power driven clamping means forclamping the upper die set to the platen so that manual operations inconnection with securing the upper portion of the die set to the platenare eliminated.

From the foregoing it will be evident that a primary object of thepresent invention is the provision of a greatly improved sliding bolsterpress having automatic die clamping means associated with the platen.

A still further object of the present invention is the provision of animproved sliding bolster type press having automatic clamping meanscarried by the platen and a detector for detecting the height of the dieset to be 3,225,686 Patented Dec. 28, 1965 clamped on the press andcontrolling the positioning of the press platen.

Still another object of this invention is the provision of a slidingbolster press having detector means for detecting the height of the dieset and adjusting the platen in conformity therewtih, and includingcontrol means for the sliding bolster so that it will automatically haltin its movement in the press during the aforementioned detectingoperation.

The foregoing objects as well as still other objects and advantages ofthe present invention will become more apparent upon reference to thefollowing specification taken in connection with the accompanyingdrawings in which:

FIGURE 1 is a somewhat diagrammatic front elevational view of a slidingbolster press according to the present invention.

FIGURE 2 is a plan sectional view indicated by line 2--2 on FIGURE 1showing the bed of the press and the sliding bolsters with the slidingbolsters both in their outermost position.

FIGURE 3 is a diagrammatic vertical sectional view indicated by line 33on FIGURE 1 showing in some detail the clamping arrangement for theupper portion of the die and also showing the drive to the bolster plateand the clamping of the bolster plate to the bed of the press.

FIGURE 4 is a transverse section indicated by line 4-4 on FIGURE 3.

FIGURE 5 is a sectional view indicated by line 55 on FIGURE 4 showing aclamp approaching the top plate of a die which is to be clamped to thepress slide.

FIGURE 5ais a view similar to FIGURE 5 which shows the clamp in theposition it occupies when the plate is clamped to the slide.

FIGURE 6 is a side elevational view of the press bed drawn at somewhatenlarged scale and showing the fluid operated clamp motor for clampingthe bolsters to the bed and the connections of this motor with theclamping devices that engage the sliding bolsters.

FIGURE 7 is a vertical sectional view indicated by line 7-7 on FIGURE 3showing a clamping arm associated with the bolster clamping structure.

FIGURE 8 is a sectional view indicated by line 8-8 on FIGURE 3 andshowing other details in connection with the bolster clampingarrangement.

FIGURE 9 is a fragmentary sectional view indicated by line 9-9 on FIGURE2 and showing an aligning key means for eifecting precise alignment ofeach bolster in the press when the bolster is set down in workingposition in the press.

FIGURE 10 is a diagrammatic sectional view showing the adjustableconnection of the slide to the connecting rods.

FIGURE 11 is a diagrammatic view of an arrangement according to thepresent invention showing a die set loaded on the left hand bolster andready to be moved into working position in the press.

FIGURE 12 is a view like FIGURE 11 but shows the bolster together withthe die set thereon moved into deflecting position in the press and withthe press slide in the process of being adjusted to proper position forreceiving the die set.

FIGURE 13 is a view similar to FIGURES 11 and 12 but showing the bolstermoved completely into the press into working position therein andclamped to the press bed.

FIGURE 14 is a diagrammatic view similar to FIG- URES 11 thru 13 butshows the press slide lowered into position for clamping the slide tothe top plate of the upper portion of the die set.

FIGURE 15 is a somewhat diagrammatic perspective view showing one formwhich the pendulum detector arm can take.

FIGURE 16 is a somewhat simplified diagrammatic representation of anelectric control circuit for controlling the operation of the press andthe actuation of the bolsters and the clamps andthe measuring circuitforming a part of the present invention.

Referring to the drawings somewhat more in detail, the press accordingto the present invention comprises the usual bed and a head 12 withuprights 14 being provided between the head and the bed. Power meanscarried by the head is operable for reciprocating platen 16 which iscarried in the usual manner on the press uprights. The particular drivemeans for the platen is not shown, but it will be understood to comprisea reversible motor connected with a crank shaft having connecting rodmeans leading to the platen.

The connecting rod means are so arranged that the effective lengththereof can be adjusted thereby to change the region of movement of theplaten. This can be done by forming the connecting rod means of portionsthreaded together or by having the connecting rod means terminate in ascrew that is threaded into nuts carried by the platen. By rotating thenuts, the platen can be raised or lowered for any given position of thedriving crankshaft. The exact manner in which this is done will bedescribed hereinafter.

The press bed 10 is adapted for receiving bolsters, one of which isindicated at 18 in FIGURE 1. In FIGURE 2 it will be observed that inaddition to bolster 18 there is a second bolster 2t) and that each ofthese bolsters is movable into and out of the press from the sidethereof. Bolster 18, when moved out of the press is received on asupport platform 22, whereas bolster 20, when it is moved out of thepress is received on a supporting platform 24.

Each bolster is provided with wheels 26 on the opposite side which runin tracks 28 formed in the platform above referred to so that thebolsters will move in a predetermined path into and out of the press.The press bed similarly is provided with tracks 30 which form acontinuation of tracks 28 so that the bolsters are guided throughouttheir movement into and out of working position in the press and can bemoved relatively easily.

For moving the bolsters, each is provided on the bottom side thereofwith a slot 32 in the side of which is mounted a long rack 34. This rack34 meshes with a pinion 36 mounted on the output shaft of a speedreducer 38, the input shaft of which is driven by a motor 40. As will beseen in FIGURE 2, there is a drive unit for each of the bolsters so thatthey are operable independently of each other.

During the time that the bolsters are moving into and out of the press,they are supported on their respective rollers and are otherwise inspaced relation to the supporting platform and the press bed. When thebolsters reach working position in the press bed however, it isdesirable for them to be set down on the bed as illustrated in FIGURE 3so that a firm bearing of the bolster on the press bed will be had inorder to transmit pressing forces directly to the press bed. Forpermitting the bolsters to set down on the press bed, the press bedincludes vertically movable track sections on which the rollers 26 aredisposed when the bolster is in working position. These movable tracksections will be seen at 42 in FIGURES 3, 7 and 8. These sectons arenormally flush with the remainder of the guiding track portions and aremoved downwardly when the bolster is in position thereby to lower thebolster to the press bed whereby the bolster is firmly supported by thepress bed.

The mechanism for moving the track sections vertically will be seen inFIGURES 1-3 and 68 and particularly in FIGURES 3, 7 and 8. Thismechanism comprises an angular arm 44 pivoted adjacent each movabletrack section and having a portion 46 connected by pivot means 48 withthe pertaining track section. Each arm has another portion 50, whichother portions are interconnected by an adjustable drag link 52 so thatthe arms will move in unison. One of the arms has a projecting portion54 connected to the ram of a double acting fluid motor 56. When themotor is actuated in one direction, it elevates the track sections andsupports them so that they form roller receiving surfaces flush with theremainder of the track sections, whereas when the motor is actuated inits other direction, the track sections are moved to their loweredposition to lower the bolster to the bed.

As will be seen in FIGURE 6, each arm 44 is fixed to a shaft 58 andthese shafts extend completely through the bed and have fixed to theirother ends corresponding arms 44 for actuating corresponding tracksections at the opposite side of the bed. These other arms 44 are alsoconnected by an adjustable drag link 52 so that all of the tracksections are fixed together and will operate in unison.

Incorporated in each movable track section is a clamping arrangement forclamping the bolster in its lowered position. These clamping portionscomprise the hook elements 60 formed on the movable track sections anddefining a groove for receiving the projections 62 formed on the members64 that are secured to the sides of the bolsters and support the outerends of the axles of rollers 26. When the bolster is in position, theprojecting portions 62 are located in the grooves defined by the hooks60 so that when the track sections are moved, the hooks 60 clampinglyengage the projecting portions 62 and lock the bolster to the bed.

To demonstrate the lowering and clamping action referred to above, inFIGURE 3 at the left side, the track section and the bolster areillustrated in elevated position, whereas at the right side of thisfigure, the track section and bolster are illustrated in loweredposition with the aforementioned clamping action taking place.

Each of the track sections is vertically slidable in a space indicatedat 66 in FIGURES 7 and 8, and this space is availed of for receiving theadjacent roller 26, as will best be seen in FIGURE 8, and this providesa sort of rest for the roller which assists in locating the roller andthereby for locating the bolster so that the operation of lowering thetrack sections and clamping the bolster in place will also serve toeffect location of the bolster in the bed. i The actual precisionlocating of the bolster in the press, however, is accomplished by theprovision of hardened keys or locater rings 70 set into the press bed,as are indicated generally in FIGURE 2 and in section in FIG- URE 9. Forcooperation with these hardened keys 70, each bolster has formed on thebed a hardened plug-like key 72 pertaining to one of the locator rings.In FIG- URE 9 it will be noted that each key 72 is tapered at an angleof say, 30, so that slight misalignment of the keys and rings will becompensated for when the bolster sets down on the bed, and it will beguided into exact position on the bed when it is set down and clampedthereto. As will be seen in FIGURES 3, 4 and 5, the press platen 16 isprovided on its underneath side with a plurality of laterally extendingT-shaped grooves 80. These grooves are availed of for slidably receivingsupport blocks 82, which form portions of a clamping arrangement forclamping the upper portion of a die set to the press platen. Eachsupport block 82 is connected to a pertaining screw 84 that extends fromthe outside face of the platen to the region of the center thereof whereit is rotatably received in a support block 86 fixed to the platen. Atits extreme outer end each screw 84 is connected through a self-lockingworm drive 88 with a pneumatic torque motor 90, or similar source ofrotating power such as an electric motor. The torque motors 90 cantherefore be availed of for reversibly driving screws 84, which willcause blocks 82 to move toward and away from the center of the pressplaten. The self-locking worm drive 88 pertaining to each'screw willlock it in its adjusted position when the pertaining block through motor90 is de-energized.

Each support block 82 comprises a dependent portion 92 formed with arecess opening toward the center of the platen and at its bottom havinga wall portion inclined upwardly toward the outside of the press andformed to define a dove tail guide way 94. Mounted on each dove tailguide way is a clamp block 96 which has its upper face formed in twohorizontal steps, the lower one of which i toward the center of thepress.

Each clamp block 96 is retained on its pertaining support block 82 by ascrew 98 which provides for movement of the clamp block on itspertaining dove tail guide way so that when the clamp block is moved onits guide way it will either move toward or away from the lower surfaceof the platen. Spring means associated with each clamp block urgesdownwardly on its pertaining dove tail guide way.

As will be seen in FIGURES l and 4, there may be six of theaforementioned support blocks 82 and clamp blocks 96 pertaining theretoon each side of the press, and these are availed of for clampingtheupper portion of the die sets of various sizes to the press platen. Aswill be explained more fully hereinafter, the die sets are moved intoworking position in the press by movement of the bolster on which thedie set is mounted into working position, and the platen isautomatically adjusted to such a height that movement of theaforementioned clamping device inwardly toward the center of the platenwill bring the pertaining clamp blocks into engagement with the sideedges of the plate on the top of the upper die set and because of theinclined surfaces supporting the clamp blocks, the clamp blocks willmove upwardly and clamp the aforementioned plate tightly to the pressplaten. The aforementioned self-locking worm drives will hold theclamping device in position.

Further, in order to accommodate the press to die sets of differentsizes, the clamping devices can be operated in groups so that forclamping small die sets in the press, only as many clamping devices asare necessary may be operated. This type of clamp allows for a range ofsizes of dies both left to right and front to back dies. Cther dieclamps on market do not allow for this but must have a die adapter plateof the same size for every die used in the press.

An important feature of the present invention is to be found inconnection with the automatic adjustment of the press platen to theproper height for receiving the die set therein. The particular mannerin which this is accomplished will be explained in detail in connectionwith the electrical control circuit for the press but reference toFIGURES 11 thru 14 will serve to indicate in general what takes place.

Reference to FIGURES 11 thru 14 will show what takes place in themounting of a die set in a press according to this invention.

In FIGURE 11 the left hand bolster 18 is provided with a die setgenerally indicated at 104 and illustrating that the lower part 106 ofthe die set is already fixed to the bolster plate as by the bolt orclamp means 108. The upper portion 110 of the die set includes aclamping plate 112 at the top thereof.

In FIGURE 11 the press slide 16 is shown at the top of its stroke, andthe dotted line 114 shows the position which the slide would occupy atthe bottom of its stroke. It will be noted that this lowermost positionof the slide is too low for receiving the die set.

FIGURE 12 shows that bolster 18 has been moved toward the center of thepress until the center of the die set is about directly beneath thependulum detector or measuring arm 116 pivotally suspended at 118 at thetop of the side opening of the press frame. This detector arm isdeflected by the die set to an angle that corresponds to the height ofthe die set.

By means of a measuring circuit to be described hereinafter, thedeflection of the measuring arm together with the actuation of the limitswitch LDS which is engaged by cam 18 on the bolster 18 in its FIGURE 12position, makes the measuring system effective and this will producemovement of the press slide in the proper position to bring aboutadjustment of the lowermost position thereof for receiving the die set.In the particular case illustrated, since the bottom position of theslide is too low for receiving the die set, the slide is adjustedupwardly as indicated by arrow 120. When the slide adjusts upwardly to aposition where its lowermost position when the slide is at the bottom ofits pressing stroke will receive the die set, the adjustment isterminated automatically, and the bolster can then move into workingposition, and is automatically clamped to the bed.

FIGURE 13 shows the bolster 18 moved into working position and with thebolster clamped tight against the press bottom by the clamps previouslyreferred to and which clamps are formed on the movable track sections42.

After the bolster 18 has reached working position in the press and thebolster is clamped to the press bottom, the press slide is moved to itsbottom stroke position, which position is illustrated in FIGURE 14, andthereafter the several clamps carried by the slide are actuated to clampthe top plate of the upper portion of the die set to the press slide.

The nature of the particular detector arm referred to above will bebetter seen in FIGURE 15 wherein the arm 116 will be seen to beassociated with a resistor element 139 by way of a movable arm 132. Thisarm moves along the resistor element as the pivot type detector arm 116is moved in detecting the height of the die set being put in the press.

As will be seen in the drawings, there is a detector element located ineach of the side openings of the press so that die sets can beintroduced into the press from either side and automatic adjustment ofthe minimum daylight openings of the press will take place for receivingthe particular die set.

In connection with the adjustment of the press platen or slide inresponse to deflection of either of the detector arms, what occurs isthat a reversible electric motor 120 (FIGURE 10) operates through adrive train 122 to actuate a nut 124 threadedly engaging a screw 126pinned by a pin 128 to the lower end of connecting rod 131, the upperend of which is connected to a throw of the drive crankshaft of thepress. Nut 124 is clamped in the platen or slide 16 by clamp means 133so that, as the nut rotates, the effective length of the pertainingconnecting rod is adjusted. Normally, there are at least two of theconnecting rods 131, and each will have a screw and nut associatedtherewith.

Reference now to the FIGURE 16 will show how the automatic operation ofthe press is carried out.

In FIGURE 16 the power lines are indicated at L1 and L2, and connectedtherebetween is the reversible motor 134 connected for drivingcrankshaft 136 that causes reciprocation of the slide 16 in the pressframe. Motor 134 is controlled in its forward direction when the pressis operating normally by relay R1, which is adapted for being energizedby closing of the switch 137. The relay can be deenergized by openingstop switch 138. The cycle of the relay according to any predeterminedpattern or schedule can be accomplished by a control arrangement 140 ofconventional design which can provide for single cycle operation of thepress or manual operation thereof or automatic or any other mannerdesired.

Motor 134 is also adapted for being controlled in its forward directionby switch 142 which will cause the motor to run in the forward directionuntil limit switch LS2 is opened by the crankshaft at the uppermostlimit of its travel. Similarly, a switch 144 can be employed for runningmotor 134 in the reverse direction, and the motor will run in thisdirection until the slide reaches the bottom of its stroke when thecrankshaft opens limit switch LS3 and stops motor 134.

As has been mentioned before, each bolster has as sociated therewith itsown individual driving motor.

Motor 40 pertains to the left hand bolster 18, while the motor 41pertains to the right hand bolster 20. Each of these motors isreversible for selectively driving the bolster into or out of the press.

For controlling bolster motor 40 there is a relay R2 which, uponenergization by closing switch 159, will cause the bolster motor 40 torun in a direction to move bolster 18 toward the center of the press.Relay R2 has a holding circuit extending through limit switch LBIpositioned for being opened by bolster 18 when it is in workingposition, so that the relay R2 will automatically be deenergized whenbolster 18 reaches Working position in the press.

Movement of the left hand bolster outwardly is accomplished byenergization of relay R3 which can be energized by closing of switch154. The holding circuit for the coil of relay R3 is completed through ablade of limit switch LBO, which is positioned to be actuated into openposition by the left hand bolster in its outer position.

The right hand bolster 20 has an arrangement for reversibly energizingits drive motor 41 which is identical with that for bolster 18. Thearrangement for bolster 20 includes the bolster in relay R4 energizableby switch 156 and having limit switch RBI in its holding circuit. Theright hand bolster out relay is R5 which is energized by switch 158 andwith a limit switch RBO in the holding circuit.

In order to carry out the die height detecting operation, however,energization of either of the bolster in relays R2 or R4 will not beaccompanied by complete inward movement of the pertaining bolster; butinstead, the pertaining bolster will come to a halt in an intermediatedetecting position with the detecting arm engaging the top of the dieset. This is brought about by actuation of the pertaining one of limitswitches LDS or RDS, the former pertaining to the left hand bolster andthe latter pertaining to the right hand bolster.

These switches which will be seen in FIGURE 11, are actuated duringinward movement of the pertaining bolster by respective cams 18a and 20awhen the pertaining bolster reaches detecting position, but are passedidly by the said cams of the bolsters when they are moving outwardlyfrom the press. It would also be possible to make these switchesineffective during outward movement of the bolsters by arrangingnormally closed contacts of relays R3 and R5 in the circuit to timer T.Closure of either of limit switches LDS or RDS will complete a circuitto a timer T.

When the timer is energized, a blade T1 closes and completes a circuitto the coil of a relay R6, which closes its blade 160 to complete acircuit to a bridge circuit 162 which forms the measuring device fordetecting the die height. Also blades 161 and 163 in circuit with motorsand 41 open and the motor which is running will come i to a halt. Bridgecircuit 162 has in one of its legs thereof the resistances 130L and 130Rpertaining to the detector arms 116L for the left hand side of the pressand 116R for the right hand side of the press, respectively. Theresistances 130R and 130L are arranged for being made selectivelyeffective by including in circuit at 130R a normally open blade of relayR2, and by including in circuit with resistance 1361. a normally openblade of relay R4. In this manner only the adjustable resistorpertaining to the side of the press into which a bolster is being movedwill be effective.

In another leg of the bridge is a resistance 164 that is provided withan adjustable slide contact 166 that is connected to the slide adjustingmotor 120 for being ad justed thereby.

Any condition of unbalance established in the bridge circuit 162 bydeflection of one or the other of the detector arms 116L or 116R will bereflected in a voltage difference across the bridge terminals, which canbe utilized for actuating one or the other of relays R7 or R7. R7 willbe energized for a condition of unbalance in one direction, indicating,for example, a die height above a predetermined amount, whereas R7 willbe'energized to indicate a die height below a predeterminad amount.Relay R7 when energized, closes its blade 168 and energizes slide motor120 in a direction to cause the slide to move upwardly relative to thecrankshaft. Relay R7, on the other hand, when energized, closes itsblade 1 and this will cause slide motor to run in a direction to adjustthe slide downwardly relative to the crankshaft.

Relay R7 has another normally closed blade 172 which is in series with asecond normally closed blade 174 of relay R7. These blades are incircuit with a blade T2 of timer T and the coil of a relay R8. Timerblade T2 is arranged to close some time after the closing of theaforementioned time plate T1 so that, after the energizing circuit ismade effective, timer blade T2 will close. But at this time, if anadjusting cycle is taking place, closing of blade T2 will be withouteflect. However, upon the adjusting operation being completed and acondition of balance being established in bridge circuit 162, both ofrelays R7 and R7 will be de-energized, and this will complete a circuitthrough timer blade T2 to the coil of relay R8, causing this relay toopen and its blade 176 to open, which is in circuit with the coil ofrelay R6. This will de-energize relay R6, which will close blades 161and 163, which will again energize the bolster motor of the bolster thatis moving into the press, whereupon the bolster will continue toward thecenter of the press.

As soon as the bolster runs 011 the one of limit switches LDS and RDSwhich is closed, timer T will be de-energized and its pertaining bladeswill open.

At this time the bolster is ready to be clamped to the bed and thesolenoid S1 pertaining to the valve 56a connected to the bolster clampis energized. Solenoid S1 is connected for being energized by a circuitwhich passes through a normally closed blade 180 of the right handbolster out switch 158 and a normally closed blade 182 of the left handbolster out switch 154. From blade 182 the circuit extends to a contact184 which is closed by switch LBI when the left hand bolster iscompletely in. From a point between blades 180 and 182 there is aconnection to a second contact 186 of limit switch RBI that is closedwhen the right hand bolster is completely in.

The movement of either bolster to working position in the press willthus cause energization of the clamp sole noid S1, whereas thedepressing of either of the bolster out switches 154 and 158 will effectde-energization of the clamp solenoid S1 so that the bolster will beunclarnped and can move out of the press. As soon as either bolstercommences to move out of working position in the press, its pertainingswitch LBI or RBI will drop closed and thereafter the clamp solenoidwill remain de-energized.

In the manner described above, either bolster can be selectively movedinto or out of the press and will be automatically clamped to the pressbed when it reaches working position and, also, each bolster will stopin an intermediate position when moved into the press and an automaticdetection and measuring and slide adjusting operation will take place atthe completion of which the bolster will continue its movement intoworking position in the press.

After the bolster carrying a die set has been moved into workingposition in the press, the crankshaft 136 is operated to its down strokeposition, as by operation of switch 144 and, on account of theadjustment of the slide during the aforementioned detection operation,the slide will be positioned close to the top plate of the upper part ofthe die set and will either be in position for clamping to the slide,or, at the most, a minor adjustment of the slide will be necessary tobring it into the proper position for attaching the upper part of thedie set thereto- In connection with any manual adjustments necessary onthe slide motor, the manual switches 190 and 192 can be availed of forreversibly energizing motor 120.

With the bolster carrying the die set now in working position in thepress and clamped to the bed, and with the press slide moved to its downstroke position and, if necessary, adjusted to a position close to oreven engaging the top plate of the upper die set, the clamping operationcan now be carried out. This is done by actuating the clamp motors 90 tomove the clamps inwardly to engage the edges of the top plate of theupper part of the die set. Inasmuch as die sets will vary in size, anarrangement is provided for actuating only the number of clamps that arerequired to hold the die set in place.

This is done, as will be seen in FIGURE 16, by a selector switch 200which is movable from an off position into any of three other positions,in the first of which four of the clamp motors 90 can be made effective,in the second of which eight of the clamp motors can be made effective,and in the third of which twelve of the clamp motors can be madeeffective. In the drawing it will be understood that there are reversingvalves pertaining to the clamp motors and that these are double solenoidoperated so that what the switch 200 controls is the groups of solenoidspertaining to the valves of the motors to be actuated and specifically,the solenoids which produce inward movement of the clamp motors.

The solenoids pertaning to the valves that produce outward movement mayall be connected in parallel so that all of the clamps will move outwardsimultaneously. As mentioned, the motors 90 are pneumatically operatedstall motors and can come to a halt when energized without there beingany damage to the motor or the parts which it is driving.

In the clalnp circuit the clamping is effected by adjusting switch 200to the desired position and then closing a switch 202 which completes anenergizing circuit to an air valve control solenoid 204 which willinitiate a supply of air for the valves of the clamping motors. Switch266 is then closed and this will effect energization of the ones of thesolenoids which will produce inward movement of the clamps that areselected by the switch 2%. The selected clamps will then move inwardlyand enga e the edges of the top plate of the die, as will be seen inFIGURE 5. When the clamps are driven completely inwardly, the clampblocks 96 ride up their inclines and pull the aforementioned top platetightly against the surface of the slide.

According to the present invention, the clamping of the too late is thenmade secure by closing a switch 208 which energizes the timer TC. Thistimer has blades T01 and TC2 whi h operate simultaneously and which,upon energization of the switch 208 in the slide, will deenergize theclamp in solenoids and energize the clamp out solenoids. The insolenoids are under the control of blade TC1 and are indicate-d at 210.and the out solenoids are indicated at 212. This operation of the bladesTCl and TC2 will bring about a short retracting movement of the clamp,and thereafter blades TC]. and TC2 will cooperate to again de-energizethe out solenoids and energize the in solenoids, and the clamps againwill be driven against the top plate of the die set and the clamping ofthe die set to the press slide has thus been made certain. The screws 84will hold the clamp blocks in adjusted position so that there is notendency for the top plate to come loose from the slide. However, inorder to prevent any accidental loosening of the top plate from theslide, timer TC has a third blade TC3 which, following theaforementioned action of retracting and then advancing the clamp blocks,opens the circuit leading to the air valve solenoid 204 and closes acircuit to a motor 214.

Motor 214 drives a cam 216 which periodically closes a switch 213 toeffect energization of the valve solenoid ZlD-l on a cyclic basis. Withthis arrangement there is a periodic supply of air under pressure to theair motors to set the clamps tightly in the event that any thereof haveloosened, and immediately after this the air is again cut Off untilswitch 218 is closed. This provides for periodic 3Q checking of thetightness of the clamps, and requires little power, and represents anadvantageous safety feature in connection with the automatic clampingarrangement of the present invention.

The present invention thus provides for a simple rapid labor-savingarrangement for changing dies in a press, and an arrangement which isparticularly conserving of the press working time, because a minimumamount of press down time is required for changing dies. The new die tobe put into the press is secured to the bolster plate which is out whilethe press is still working and, when the new die is to be put into thepress, the press slide is moved to its down stroke position, the old dieis unclamped by operation of the clamp motors by closing switch 207, theplaten is then moved to its up stroke position, the bolster that is inthe press is then move-d out of the press, and the bolster that is outof the press is then moved toward the center of the press. As explainedbefore, the bolster moving into the press will halt in an intermediateposition while a measuring and slide adjusting operation takes place.When this adjusting operation is completed, the bolster moves on intoworking position and the press operator can then move the slide to downstroke position, make any minor adjustments necessary to the slideposition, clamp the new die set in place to the press slide, and thepress is ready to be placed in operation.

All the foregoing steps can be carried out rapidly and conveniently sothat not only is labor saved, but harmful accidents are avoided, whichmight damage expensive die sets or cause injury to personnel and themaximum working time of the press is available.

It will be understood that this invention is susceptible tomodifications in order to adapt it to different usages and conditions;and accordingly, it is desired to comprehend such modifications withinthis invention as may fall within the scope of the appended claims.

I claim:

1. In a sliding bolster press; a press bed having track means extendingthereacross, support means extending from the bed and including trackmeans linearly coplanar with the bed track means, bolster means havingprojections on the sides thereof and also having support rollersengaging said track means for movement or the bolster means into and outof the press, said bed track means having vertically movable sections onwhich the rollers rest when the bolster means is in working position onthe bed, said vertically movable sections also having clamping meansadaptable for engaging said projections, there being at least four ofsaid rollers and four said sections, an actuating arm for each section,shafts extending through the bed interconnecting each said arm on oneside of the bed with an arm on the other side of the bed, links on eachside of the bed interconnecting all of the arms on the same side of thebed, and a motor connected to said arms for the simultaneous actuationthereof, each said actuating arm being adaptable to lower and raise thepertaining vertically movable section to simultaneously lower and clampthe said bolster means to said bed and to simultaneously raise andunclamp said bolster means.

2. In a sliding bolster press; a press frame comprising a bed, a head,uprights, a slide guided on the uprights, and slide actuating means inthe head, a bolster and means supporting the bolster for movement intoand out of the press to and from working position on the bed, probemeans engageable with a die set on the bolster as the bolster is movedinto the press to detect the height of the die set, connecting rod meansconnecting the slide to the actuating means and adjustable in length,and means operated by the probe means for adjusting the length of theconnecting rod means so the slide in its downstroke position will be inconformity with the height of the die set.

3. In a sliding bolster press; a press frame comprising a bed, a head,uprights, a slide guided on the uprights, and slide actuating means inthe head, a bolster and means supporting the bolster for movement intoand out of the press to and from working position on the bed, probemeans engageable with a die set on the bolster as the bolster is movedinto the press to detect the height of the die set, connecting rod meansconnecting the slide to the actuating means and adjustable in length,and a reversible electric motor connected to the connecting rod means toadjust the length thereof, an energizing circuit for said motorcomprising a bridge circuit, and means operated by the probe means forcontrolling said circuit to energize the motor for adjusting the lengthof the connecting rod means so the slide in its downstroke position willbe in conformity with the height of the die set.

4. In a sliding bolster press; a press frame comprising a bed, a head,uprights, a slide guided on the uprights, and slide actuating means inthe head, a bolster and means supporting the bolster for movement intoand out of the press to and from working position on the bed, and probemeans engageable with a die set on the bolster as the bolster is movedinto the press and operable to adjust said slide relative to the saidactuating means to conform the downstroke position of the slide to theheight of the die set, power means carried by the bed for driving thebolster to and from working position in the press, and meansautomatically operable during movement of the bolster into the press forinterrupting movement of the bolster after the probe means is engagedtherewith for carrying out of the slide adjustment while the bolster isstationary, and then resuming movement of the bolster into the press.

5. In a press having a bed and a slide; means for locating a die set inworking position on the bed, said die set having an upper part with aclamp plate for clamping it to the slide, guideways on the slide, clampmembers movably carried by the guideways, a screw carried by the slideextending along each guideway and threaded to the pertaining clampmember,'a stall motor on the slide for each screw, and means forreversibly energizing said motors for moving the clamp members inclamping and unclamping directions.

6. In a press having a bed and a slide; means for locating a die set inworking position on the bed, said die set having an upper part with-aclamp plate for clamping it to the slide, guideways on the slide, clampmembers movably carried by the guideways, a screw carried by the slideextending along each guideway and threaded to the pertaining clampmember, a stall motor on the slide for each screw, and means forreversibly energizing said motors for moving the clamp members inclamping and unclamping directions, each clamp member comprising asurface inclined downwardly toward the center of the press, and a clampelement on said surface having a step on the side toward the center ofthe press whereby engagement of a clamp plate by a clamp element willpush the clamp element up the pertaining surface and clamp the plate tothe slide.

7. In a press having a slide; slots extending across the slide, twoclamp members in each said slot sli-dably mounted therein, a screwextending along each said slot from each side of the press and screwthreaded to one of the clamp members, a reversible motor on the slideconnected to each screw, and means for reversibly energizing said motorsin predetermined groups.

8. In a press having a slide; slots extending across the slide, twoclamp members in each said slot slidably mounted therein, a screwextending along each slot from each side of the press and screw threadedto one of the clamp members, a reversible air motor on the slideconnected to each screw, and means for selectively reversibly energizingsaid motors, each clamp member comprising a block supported in thepertaining slot and threaded to the pertaining screw and having aguideway on the side toward the center of the press inclined downwardlytoward the center of the press, a clamp element on said guideway havinga step on the side toward the center of the press, and means biasing theclamp element downwardly on the guideway.

9. In a press having a bed and slide; means for locating a die set inworking position on the bed, said die set having an upper part with aclamp plate for clamping it to the slide, guideways on the slide, clampmembers movably carried by the guideways, a screw carried by the slideextending along each guideway and threaded to the pertaining clampmember, a stall motor on the slide for each screw, means for energizingsaid motor to run in the clamping direction to clamp said clamp plate tothe slide, means for interrupting the supply of energy to said motorfollowing the clamping thereof, and means operable for periodicallysupplying energy to said motor for insuring that the clamp membersremain in clamping position during operation of the press.

10. In a press having a slide; slots extending across the slide, twoclamp members in each slot slidable therein, a screw extending alongeach slot from each side of the press and screw threaded to one of theclamp members, a reversible air motor on the slide connected to eachscrew, valve means connecting said motors and adapted for connection toa source of air under pressure, means for shifting said valve means tobring about a supply of air to said motors to drive the clamp members inclamping direction, means for interrupting said supply of air after theclamp members are in clamping position, and time controlling means forperiodically supplying air from said source to said valve means duringoperation of the press to make certain that the clamp members remain inclamping position.

11. In a sliding bolster press; a press frame comprising a bed, a head,uprights, a slide guided on the uprights, slide actuating means in thehead, connecting rod means connecting the slide actuating means with theslide and adjustable in length, bolster support means extendinglaterally from the press bed, a bolster on said support means movabletherefrom to said bed and vice versa, power operated means in the bedoperatively connected with the bolster for effecting the said movementthereof, a motor means connected with said connecting rod meansreversibly operable for adjusting the length thereof, probe meanscarried by the press frame and depending in the space through which adie set carried by the bolster will move, means for energizing saidpower operated means for effecting movement of the bolster toward thepress bed, means operated by the bolster for bringing the bolster to ahalt with the probe means resting on the die set on the bolster,electric circuit means under the control of the probe means andconnected to the said motor means for adjusting the slide position inconformity with the height of the die set on the bolster, meansresponsive to the termination of the adjustment of the connecting rodmeans for resuming movement of the bolster into the press, meansresponsive to movement of the bolster into locking position in the pressfor clamping the bolster to the press bed, means for energizing saidactuating means to lower the slide to lowermost stroke position, andclamping means carried by the slide operable when energized for clampingthe die set on the bolster to said slide.

12. The press as claimed in claim 11 in which said electric circuitmeans comprises a bridge circuit and in which said motor means foradjusting the slide is a reversible electric motor.

13. The press as claimed in claim 11 in which said probe means comprisesvariable resistor means.

14. The press as claimed in claim 11 in which said bolster hasprojections on the sides thereof and in which said means for clampingthe bolster to the press bed comprises vertically movable sectionsmounted on said bed and being adaptable to engage said projections andsimultaneously lower and clamp said bolster in said bed.

15. The press as claimed in claim 11 in which said clamping meanscarried by the slide comprises, slots extending across the slide, twoclamp members in each slot slidable therein, a screw extending alongeach slot from each side of the. press and screw threaded to one of theclamp members, and a reversible motor on the slide connected to eachscrew.

16. The press as claimed in claim 11 in which said clamping meanscarried by the slide comprises slots extending across the slide, twoclamp members in each said slot slidably mounted therein, -a screwextending along each said slot from each side of the press and screwthreaded to one of the clamp members, a reversible motor on the slideconnected to each screw, and means for reversibly energizing said motorsin predetermined groups.

17. The press as claimed in claim 11 in which said clamping meanscarried by the said slide comprises; slots extending across the slide,two clamp members in each slot slidably mounted therein, a screwextending along each slot from each side of the press and screw threadedto one of the clamp members, a reversible air motor on the slideconnected to each screw, and means for selectively reversibly energizingsaid motors, each clamp member comprising a block supported in thepertaining slot and threaded to the pertaining screw and having aguideway on the side toward the center of the press inclined downwardlytoward the center of the press, a clamp element on said guideway havinga step on the side toward the center of the press, and means biasing theclamp element downwardly to the guideway.

18. The press as claimed in claim 11 in which said clamping meanscarried by said slide comprises; slots extending across the slide, twoclamp members in each slot slidable therein, a screw extending alongeach slot from each side of the press and screw threaded to one of theclamp members, a reversible air motor on the slide connected to eachscrew, valve means connecting and adapted for connection to a source ofair under pressure, means for shifting said valve means to bring about asupply of air to said motors to drive the clamp members in clampingdirection, means for interrupting said supply of air after the clampmembers are in clamping position, and time controlling means forperiodically supplying air from said source to said valve means duringoperation of the press to make certain that the clamp members remain inclamping position.

19. In a sliding bolster press; a press frame comprising a bed, a head,uprights, a slide guided on the uprights, slide actuating means in thehead, connecting rod means connecting the slide actuating means with theslide and adjustable in length, bolster support means extendinglaterally from the press bed, a bolster on said support means movabletherefrom to said bed and vice versa, power operated means in the bedoperatively connected with the bolster for effecting the said movementthereof, a motor means connected with said connecting rod meansreversibly operable for adjusting the length thereof, probe meanscarried by the press frame and depending in the space through which adie set carried by the bolster will move, means for energizing saidpower operated means for effecting movement of the bolster toward thepress bed, means operated by the bolster for bringing the bolster to ahalt with the probe means resting on the die set on the bolster, andelectric circuit means under the control of the probe means andconnected to the said motor means for adjusting the slide position inconformity with the height of the die set on the bolster.

References Cited by the Examiner UNITED STATES PATENTS 97,872 12/ 1869Burkhardt 269-242 276,108 4/ 1883 Weston -257 X 2,033,865 3/1936 Platt100-45 2,112,869 4/1938 Thompson 100-45 2,575,672 11/1951 Miller 100-352,869,189 1/1959 Pirsig 22-35 X 2,913,946 11/1959 Ellrich 113-49 X2,984,176 5/1961 Sommer et a1. 100-295 2,996,025 8/ 1961 Georgetf.3,002,479 10/ 1961 Johansen et al. 3,107,604 10/1963 Deems 100-353,134,350 5/ 1964 Danly et a1. 113-49 WALTER A. SCHEEL, PrimaryExaminer.

CHARLES A. WILLMUTH, Examiner,

1. IN A SLIDING BOLSTER PRESS; A PRESS BED HAVING TRACK MEANS EXTENDINGTHEREACROSS, SUPPORT MEANS EXTENDING FROM THE BED AND INCLUDING TRACKMEANS LINEARLY COPLANAR WITH THE BED TRACK MEANS, BOLSTER MEANS HAVINGPROJECTIONS ON THE SIDES THEREOF AND ALSO HAVING SUPPORT ROLLERSENGAGING SAID TRACK MEANS FOR MOVEMENT OR THE BOLSTER MEANS INTO AND OUTOF THE PRESS, SAID BED TRACK MEANS HAVING VERTICALLY MOVABLE SECTIONS ONWHICH THE ROLLERS REST WHEN THE BOLSTER MEANS IS IN WORKING POSITION ONTHE BED, SAID VERTICALLY MOVABLE SECTIONS ALSO HAVING CLAMPING MEANSADAPTABLE FOR ENGAGING SAID PROJECTIONS, THERE BEING AT LEAST FOUR OFSAID ROLLERS AND FOUR SAID SECTIONS, AN ACTUATING ARM FOR EACH SECTIONS,SAHFTS EXTENDING THROUGH THE BED INTERCONNECTING EACH SAID ARM ON ONESIDE OF THE BED WITH AN ARM ON THE OTHER SIDE OF THE BED, LINKS ON EACHSIDE OF THE BED INTECONNECTING ALL OF THE ARMS ON THE SAME SIDE OF THEBED, AND A MOTOR CONNECTED TO SAID ARMS FOR THE SIMULTANEOUS ACTUATIONTHEREOF, EACH SAID ACTUATING ARM BEING ADAPTABLE TO LOWER AND RAISE THEPERTAINING VERTICALLY MOVABLE SECTION TO SIMULTANEOUSLY LOWER AND CLAMPTHE SAID BOLSTER MEANS TO SAID BED AND TO SIMULTANEOUSLY RAISE ANDUNCLAMP SAID BOLSTER MEANS.